### Function

# GLib timeout_add

#### Declaration [src]

    guint
    g_timeout_add (
      guint interval,
      GSourceFunc function,
      gpointer data
    )

#### Description [src]

Sets a function to be called at regular intervals, with the default priority, `G_PRIORITY_DEFAULT`.

The given `function` is called repeatedly until it returns `G_SOURCE_REMOVE` or `FALSE`, at which point the timeout is automatically destroyed and the function will not be called again. The first call to the function will be at the end of the first `interval`.

Note that timeout functions may be delayed, due to the processing of other event sources. Thus they should not be relied on for precise timing. After each call to the timeout function, the time of the next timeout is recalculated based on the current time and the given interval (it does not try to ‘catch up’ time lost in delays).

See mainloop memory management for details on how to handle the return value and memory management of `data`.

If you want to have a timer in the “seconds” range and do not care about the exact time of the first call of the timer, use the `g_timeout_add_seconds()` function; this function allows for more optimizations and more efficient system power usage.

This internally creates a main loop source using `g_timeout_source_new()` and attaches it to the global `GMainContext` using `g_source_attach()`, so the callback will be invoked in whichever thread is running that main context. You can do these steps manually if you need greater control or to use a custom main context.

It is safe to call this function from any thread.

The interval given is in terms of monotonic time, not wall clock time. See `g_get_monotonic_time()`.

This function is not directly available to language bindings.

The implementation of this function is provided by `g_timeout_add_full()` in language bindings.

#### Parameters

`interval`

  Type: `guint`

  The time between calls to the function, in milliseconds (1/1000ths of a second).

`function`

  Type: `GSourceFunc`

  Function to call.

`data`

  Type: `gpointer`

  Data to pass to `function`.

  The argument can be `NULL`.
  The data is owned by the caller of the function.

#### Return value

Type: `guint`

The ID (greater than 0) of the event source.